Gravitricity, an Edinburgh-based green engineering start-up, ... successfully trialled its first gravity battery prototype: a 15m (49ft) steel tower suspending a 50 tonne iron weight. Inch-by-inch, electric motors hoisted the massive metal box skyward before gradually releasing it back to earth, powering a series of electric generators with the downward drag.
The demonstrator installation was "small scale", says Jill Macpherson, Gravitricity's senior test and simulation engineer, but still produced 250kW of instantaneous power, enough to briefly sustain around 750 homes. Equally encouraging was what the team learned about their system's potential longevity.
While the Gravitricity prototype pointed upward, the company's focus is now below ground. Engineers have spent the last year scoping out decommissioned coal mines in Britain, Eastern Europe, South Africa, and Chile. The rationale, explains managing director Charlie Blair, is pretty straightforward: "Why build towers when we can use the geology of the earth to hold up our weights?"
Bicyclecamper said
12:27 PM Jun 1, 2022
The other way to redirect your excess solar from away from the grid, into something useful at home, if you haven't got batteries. Their is a unit that is adapted to your electric hot water system, and it takes all the excess power from your solar panels and heats the water in your hot water tank. The cost is about $800 for this box of goodies. I don't have the name for it, but we intend to do this ourselves sometime this year.
-- Edited by Bicyclecamper on Wednesday 1st of June 2022 12:28:37 PM
Buzz Lightbulb said
03:07 PM Jun 1, 2022
Sounds like a good idea. I image that it would be cheaper to build per kW output that pumped hydro.
Whenarewethere said
04:53 PM Jun 1, 2022
Bicyclecamper wrote:
The other way to redirect your excess solar from away from the grid, into something useful at home, if you haven't got batteries. Their is a unit that is adapted to your electric hot water system, and it takes all the excess power from your solar panels and heats the water in your hot water tank. The cost is about $800 for this box of goodies. I don't have the name for it, but we intend to do this ourselves sometime this year.
If you are talking about hot water heat pump, my parents installed one in the 1980s.
Cupie said
08:47 AM Jun 2, 2022
Looks interesting & perhaps uses less resources than current storage systems.
With the way that power prices are heading at the moment & the pittance that we are paid by Power Companies under current feed in tariffs for excess power from our roof top systems, then perhaps its timely to look at alternatives to selling to the rip off Power Companies.
I'll go back & have another look at the proposal that the guy who thwarted the AGL demerger has to change how we use roof top solar.
-- Edited by Cupie on Thursday 2nd of June 2022 08:57:17 AM
Rob Driver said
08:57 AM Jun 2, 2022
I wonder what the thought of the surrounding neighbours would be with the tower in your back yard.
It could take pride of place in the spot next to the wind generator.
All jokes aside it is not a bad idea in theory.
Similar to any non renewable power storage the weight will eventually be at the bottom and the result will be the same as a flat battery.
Wasn't there a scientist that said there is no such thing as perpetual motion.
-- Edited by Rob Driver on Thursday 2nd of June 2022 09:06:38 AM
dorian said
09:25 AM Jun 2, 2022
Rob Driver wrote:
I wonder what the thought of the surrounding neighbours would be with the tower in your back yard.
It could take pride of place in the spot next to the wind generator.
All jokes aside it is not a bad idea in theory.
Similar to any non renewable power storage the weight will eventually be at the bottom and the result will be the same as a flat battery.
Wasn't there a scientist that said there is no such thing as perpetual motion.
-- Edited by Rob Driver on Thursday 2nd of June 2022 09:06:38 AM
How many people have a decommissioned coal mine in their backyard?
As for perpetual motion, do pay attention and try to understand what is being proposed. It's the same kind of principle as pumped hydro, except that excess solar power is being transformed into potential energy using mechanical weights rather than water.
-- Edited by dorian on Thursday 2nd of June 2022 09:41:14 AM
Jaahn said
01:42 PM Jun 2, 2022
dorian wrote:
Rob Driver wrote:
I wonder what the thought of the surrounding neighbours would be with the tower in your back yard.
It could take pride of place in the spot next to the wind generator.
All jokes aside it is not a bad idea in theory.
Similar to any non renewable power storage the weight will eventually be at the bottom and the result will be the same as a flat battery.
Wasn't there a scientist that said there is no such thing as perpetual motion.
How many people have a decommissioned coal mine in their backyard?
As for perpetual motion, do pay attention and try to understand what is being proposed. It's the same kind of principle as pumped hydro, except that excess solar power is being transformed into potential energy using mechanical weights rather than water.
well there are plenty of old mines and adjacent hills, as shown in this survey done quite some years ago now. Not much action after the report as the 'will' was not there.
19 September 2017;
There are 22,000 possible sites for pumped hydro storage in Australia.
Some are near Newcastle and a lot are generally near where most people live.
I would think that a dam full of water would be a lot more stored energy than a weight. But who knows how the weight of water compares to the weight of iron ??
Jaahn
-- Edited by Jaahn on Thursday 2nd of June 2022 01:48:01 PM
-- Edited by Jaahn on Friday 3rd of June 2022 10:27:13 AM
Mike Harding said
02:04 PM Jun 2, 2022
SG of water is 1, SG of iron is about 7.5 - but that doesn't matter, energy is energy.
I saw this article some time back and initially thought it a great idea, and it may well be, but pondering on it I wonder about the complexity of the mechanics required and their associated losses. otoh I think pumped water loses about 25% of energy due to pipe friction. Maybe a combination of both? Of course water storage had the advantage of being a civic amenity. Interesting times.
Rob Driver said
04:51 PM Jun 2, 2022
Deleted.
Not my problem.
-- Edited by Rob Driver on Thursday 2nd of June 2022 05:00:52 PM
Here is an interesting concept that uses purely mechanical means to store excess solar energy:
https://www.bbc.com/future/article/20220511-can-gravity-batteries-solve-our-energy-storage-problems
Gravitricity, an Edinburgh-based green engineering start-up, ... successfully trialled its first gravity battery prototype: a 15m (49ft) steel tower suspending a 50 tonne iron weight. Inch-by-inch, electric motors hoisted the massive metal box skyward before gradually releasing it back to earth, powering a series of electric generators with the downward drag.
The demonstrator installation was "small scale", says Jill Macpherson, Gravitricity's senior test and simulation engineer, but still produced 250kW of instantaneous power, enough to briefly sustain around 750 homes. Equally encouraging was what the team learned about their system's potential longevity.
While the Gravitricity prototype pointed upward, the company's focus is now below ground. Engineers have spent the last year scoping out decommissioned coal mines in Britain, Eastern Europe, South Africa, and Chile. The rationale, explains managing director Charlie Blair, is pretty straightforward: "Why build towers when we can use the geology of the earth to hold up our weights?"
The other way to redirect your excess solar from away from the grid, into something useful at home, if you haven't got batteries. Their is a unit that is adapted to your electric hot water system, and it takes all the excess power from your solar panels and heats the water in your hot water tank. The cost is about $800 for this box of goodies. I don't have the name for it, but we intend to do this ourselves sometime this year.
-- Edited by Bicyclecamper on Wednesday 1st of June 2022 12:28:37 PM
Sounds like a good idea. I image that it would be cheaper to build per kW output that pumped hydro.
If you are talking about hot water heat pump, my parents installed one in the 1980s.
Looks interesting & perhaps uses less resources than current storage systems.
With the way that power prices are heading at the moment & the pittance that we are paid by Power Companies under current feed in tariffs for excess power from our roof top systems, then perhaps its timely to look at alternatives to selling to the rip off Power Companies.
I'll go back & have another look at the proposal that the guy who thwarted the AGL demerger has to change how we use roof top solar.
-- Edited by Cupie on Thursday 2nd of June 2022 08:57:17 AM
-- Edited by Rob Driver on Thursday 2nd of June 2022 09:06:38 AM
How many people have a decommissioned coal mine in their backyard?
As for perpetual motion, do pay attention and try to understand what is being proposed. It's the same kind of principle as pumped hydro, except that excess solar power is being transformed into potential energy using mechanical weights rather than water.
-- Edited by dorian on Thursday 2nd of June 2022 09:41:14 AM
There are 22,000 possible sites for pumped hydro storage in Australia.
Some are near Newcastle and a lot are generally near where most people live.
https://arena.gov.au/blog/there-are-22000-possible-sites-for-pumped-hydro-storage-in-australia/
I would think that a dam full of water would be a lot more stored energy than a weight. But who knows how the weight of water compares to the weight of iron ??

Jaahn
-- Edited by Jaahn on Thursday 2nd of June 2022 01:48:01 PM
-- Edited by Jaahn on Friday 3rd of June 2022 10:27:13 AM
SG of water is 1, SG of iron is about 7.5 - but that doesn't matter, energy is energy.
I saw this article some time back and initially thought it a great idea, and it may well be, but pondering on it I wonder about the complexity of the mechanics required and their associated losses. otoh I think pumped water loses about 25% of energy due to pipe friction. Maybe a combination of both? Of course water storage had the advantage of being a civic amenity. Interesting times.
Deleted.
Not my problem.
-- Edited by Rob Driver on Thursday 2nd of June 2022 05:00:52 PM